Auxiliary axle and suspension assembly

ABSTRACT

A vehicle suspension assembly includes an axle member movable between a first position and a second position, mounting brackets adapted to couple to a vehicle frame assembly, trailing arms pivotably coupled to mounting brackets and pivotably coupled to the axle member, a lift arrangement including a pair of diaphragm chambers each having a push plate and a flexible bladder, the push plate of the diaphragm chamber dividing the associated diaphragm chamber into a first compartment and a second compartment, the first compartment of each diaphragm chamber being adjustably pressurized to move the push plate of the associated diaphragm chamber, and at least one push rod defining a single longitudinal axis and connected to each push plate such that pressurization of the diaphragm chambers cause a translational movement of the at least one push rod, thereby causing the axle member to move between the first and second positions.

BACKGROUND OF THE INVENTION

The present invention relates to heavy duty vehicle suspensions andassemblies, and particularly to suspension assemblies incorporating atrailing arm-type configuration. More particularly, the presentinvention relates to an auxiliary vehicle suspension assembly adaptedfor movement between an in-use position and a storage position, andincorporating a self-steer assembly.

BRIEF SUMMARY OF THE INVENTION

One aspect of the present invention is to provide a vehicle suspensionassembly comprising a first mounting bracket adapted to couple to avehicle frame assembly, a first trailing arm having a first endpivotably coupled to the first mounting bracket, and a second end,wherein the second end of the trailing arm is located outboard of thefirst end of the trailing arm, a second mounting bracket adapted tocouple to the vehicle frame assembly, and a second trailing arm having afirst end pivotably coupled to the second mounting bracket, and a secondend, wherein the second end of the trailing arm is located outboard ofthe first end of the second trailing arm. The vehicle suspensionassembly further comprises an axle member having a first end and asecond end, an integrated first mounting arrangement coupled to thefirst end of the axle member, wherein the first mounting arrangementpivotably couples the second end of the first trailing arm to the firstend of the axle member, and wherein the first mounting arrangementcouples the first end of the axle member to the first spindle assembly,and an integrated second mounting arrangement coupled to the first endof the axle member, wherein the second mounting arrangement pivotablycouples the second end of the second arm to the second end of the axlemember, and wherein the second mounting arrangement couples the secondend of the axle member to the second spindle assembly.

Another aspect of the present invention is to provide a vehiclesuspension assembly that comprises an axle member having a first end anda second end, a first mounting bracket adapted to couple to a vehicleframe assembly, a first trailing arm having a first end pivotablycoupled the first mounting bracket, and a second end pivotably coupledto the axle member, a second mounting bracket adapted to couple to thevehicle frame assembly, and a second trailing arm having a first endpivotably coupled to the second mounting bracket, and a second endpivotably coupled to the axle member. The vehicle suspension assemblyfurther comprises an integrated first mounting arrangement coupled tothe first end of the axle member, wherein the first mounting arrangementcouples the first end of the axle member to the first spindle assembly,and wherein the first mounting arrangement couples the first air springto the first end of the axle member such that the first axle spring isadapted to extend between the first end of the axle member and thevehicle frame assembly, and an integrated second mounting arrangementcoupled to the second end of the axle member, wherein the secondmounting arrangement couples the second end of the axle member to thesecond spindle assembly, and wherein the second mounting arrangementcouples a second air spring to the second end of the axle member suchthat the second air spring is adapted to extend between the second endof the axle member and the vehicle frame assembly.

Still another aspect of the present invention is to provide a vehiclesuspension assembly that comprises an axle member having a first end anda second end, the axle member movable between a first position, whereinat least one tire coupled with the axle member contacts a groundsurface, and a second position, wherein the at least one tire is spacedfrom the ground surface, a first mounting bracket adapted to couple to avehicle frame assembly, a first trailing arm having a first endpivotably coupled to the first mounting bracket, and a second endpivotably coupled to the first end of the axle member, a second mountingbracket adapted to couple to a vehicle frame assembly, and a singletrailing arm having a first end pivotably coupled to the second mountingbracket, and a second end pivotably coupled to the second end of theaxle member. The vehicle suspension assembly further comprises a firstlift arrangement comprising a first diaphragm chamber having a firstpush plate and a flexible bladder, the first push plate of the firstdiaphragm chamber dividing the first diaphragm chamber into a firstcompartment and a second compartment, the first compartment of the firstdiaphragm chamber being adjustably pressurized to move the first pushplate of the first diaphragm chamber, a second diaphragm chamber havinga second push plate including a flexible bladder, the second push plateof the second diaphragm chamber dividing the second diaphragm chamberinto a first compartment and a second compartment, the first compartmentof the second diaphragm chamber being adjustably pressurized to move thesecond push plate of the second diaphragm chamber, and at least one pushrod defining a single longitudinal axis and connected to the first pushplate and the second push plate such that pressurization of the firstand second diaphragm chambers cause a translational movement of the atleast one push rod, wherein the at least one push rod is operablycoupled with the vehicle suspension assembly such that translationalmovement of the at least one push rod causes the axle chamber to movebetween the first and second positions.

Still yet another aspect of the present invention is to provide a methodof assembling a vehicle suspension assembly comprising providing an axleassembly having a first end including a first mounting structure and asecond mounting end, providing a first bearing block and a secondbearing block, forming a first aperture in the first bearing block and asecond aperture in the second bearing block, attaching the first andsecond bearing blocks to the first mounting structure subsequent toforming the first and second apertures, and providing a first spindleassembly coupled to the first mounting structure by a first sphericalbearing located within the first aperture and a second spherical bearinglocated within the second aperture, wherein a first kingpin assemblyextends through the first and second spherical bearings, therebycoupling the first spindle with the first mounting structure.

Another aspect of the present invention is to provide a vehiclesuspension assembly comprising an axle assembly having a first end and asecond end, a first mounting bracket and a second mounting bracket eachadapted to couple to a vehicle frame assembly, and a first trailing armhaving a first end operably coupled to the first mounting bracket and asecond end pivotably coupled to the first end of the axle assembly. Thevehicle suspension assembly further comprises a second mounting bracketadapted to couple to a vehicle frame assembly, and a second trailing armhaving a first end pivotably coupled to the second mounting bracket, anda second end pivotably coupled to the second end of the axle assembly.The vehicle suspension assembly still further comprises a first airspring assembly coupled to a first end of the axle assembly such thatthe longitudinal axis of the first air spring assembly inclines inwardlyfrom the first end of the axle assembly, and a second air springassembly coupled to the second end of the axle assembly such that alongitudinal axis of the second air spring assembly inclines inwardlyfrom the second end of the axle assembly, wherein a natural frequency ofthe suspension assembly is less than or equal to about 3 Hz.

The present inventive vehicle suspension assembly provides a durable,uncomplicated design that can be easily and quickly assembled, whilesimultaneously reducing manufacturing costs. The invention is efficientin use, economical to manufacture, capable of a long operating life, andis particularly well adapted to the proposed use.

These and other advantages of the present invention will be furtherunderstood and appreciated by those skilled in the art by reference tothe following written specification, claims, and appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a vehicle suspension assembly embodyingthe present invention;

FIG. 2 is a perspective view of the vehicle suspension assembly withwheel and hub assemblies removed;

FIG. 3A is a side elevational view of the vehicle suspension assembly ina lowered, in-use position;

FIG. 3B is a side elevational view of the vehicle suspension assembly ina raised, storage position;

FIG. 4A is a top plan view of the vehicle suspension assembly in aninline orientation;

FIG. 4B is a top plan view of the vehicle suspension assembly in aturning orientation;

FIG. 5 is a side elevational view of the suspension assembly;

FIG. 6 is a top plan view of a trailing arm;

FIG. 7 is an exploded perspective view of a trailing arm assembly;

FIG. 8 is an exploded perspective view of mounting arrangement andassociated connections;

FIG. 9A is a perspective rear view of the mounting arrangement;

FIG. 9B is a perspective front view of the mounting arrangement;

FIG. 10 is an exploded perspective view of a spindle assembly, whereinthe components of the spindle assembly are shown in dashed in anexploded state and in solid in an assembled state;

FIG. 11 is an exploded perspective view of bearing blocks and a portionof the mounting arrangement, wherein the bearing blocks are shown indashed in the exploded state and in solid in an assembled state;

FIG. 12A is a cross-sectional view of the spindle assembly and a portionof the mounting arrangement;

FIG. 12B is a cross-section view of the vehicle suspension assembly;

FIG. 13 is an exploded perspective view of an air spring assembly;

FIG. 14 is a rear elevational view of the suspension assembly;

FIG. 15A is a perspective view of a lift arrangement;

FIG. 15B is an exploded perspective view of the lift arrangement; and

FIG. 16 is a cross-section view of a dual diaphragm actuator, takenalong the line XVI-XVI, FIG. 15.

DETAILED DESCRIPTION OF EMBODIMENTS

For purposes of description herein, the terms “upper,” “lower,” “right,”“left,” “rear,” “front,” “vertical,” “horizontal,” and derivativesthereof shall relate to the invention as oriented in FIG. 1. However, itis to be understood that the invention may assume various alternativeorientations, except where expressly specified to the contrary. It isalso to be understood that the specific devices and processesillustrated in the attached drawings, and described in the followingspecification are simply exemplary embodiments of the inventive conceptsdefined in the appended claims. Hence, specific dimensions and othercharacteristics relating to the embodiments disclosed herein are not tobe considered as limiting, unless the claims expressly state otherwise.

A suspension assembly 10 (FIGS. 1 and 2) comprises a pair of mountingbrackets 12 fixedly connected to a pair of longitudinally extendingframe members 14 of a vehicle frame assembly and coupled to one anotherby a cross member 15, a plurality of trailing arm assemblies including apair of upper trailing arms 16 (FIGS. 3A-4B) and a pair of lowertrailing arms 18, an axle assembly 20, and a pair of air springassemblies 22 extending between the axle assembly 20 and correspondingframe members 14.

In the illustrated example, each upper trailing arm 16 (FIG. 5) includesa first end 24 pivotably coupled to one of the mounting brackets 12 forrotation about a pivot point 26 and a second end 28 pivotably coupled tothe axle assembly 20 for rotation about a pivot point 30, as describedbelow. Each lower trailing arm 18 includes a first end 32 pivotablysecured to a mounting bracket 12 for pivoting about a pivot point 34,and a second end 36 pivotably coupled to the axle assembly 20 forpivotable movement around a pivot point 38, also as described below.FIGS. 4A and 6 illustrate the generally outward-sweeping shape of thetrailing arms 16, 18 along the length of the trailing arms 16, 18 fromthe first end 24, 32 to the second end 28, 36. As best illustrated inFIG. 7, each end 24, 28, 32, 36 of the trailing arms 16, 18 arepivotably secured to the mounting brackets 12 and axle assembly 20 by abushing assembly 40 comprising a elastically resilient bushing member42, a bushing pin 44 and nylon washers 46 received within acorresponding bore 48.

As best illustrated in FIG. 8, the second end 28, 36 of each trailingarm 16, 18 are pivotably coupled to an integrated corresponding mountingarrangement 50. Each mounting arrangement 50 (FIGS. 9A and 9B) includesa triangularly-shaped rear plate 52, an L-shaped front plate 54 thatcooperates with the rear plate 52 to form an inwardly-opening pocket 56within which an end 57 of an axle member 58 of the axle assembly 20 isreceived. The rear plate 52 and the front plate 54 each include awelding aperture 60 about which a weld is formed to secure the end 57 ofthe axle 58 within the pocket 56. Each mounting arrangement 50 furtherincludes a C-shaped spindle attachment plate 62 that is attached to therear plate 52, and which cooperates with the rear plate 52 and the frontplate 54 to form a pocket 64 within which the second ends 28, 36 of thetrailing arms 16, 18 are pivotably secured. As utilized herein, the term“integrated” means that the components of the mounting arrangement 50,including the rear plate 52, the front plate 54 and the spindleattachment plate 62 are brought together with one another such that thecomponents form a single unit and are not spaced from one another. Inthe illustrated example, the rear plate 52, the front plate 54 and thespindle attachment 62 are welded to one another, however thesecomponents may also be formed as a single integral piece, or coupledtogether with various mechanical fasteners. Spindle assemblies 66 (FIGS.2 and 10-12A) are pivotably secured to the corresponding mountingarrangement 50 of the axle assembly 20 by a pair of bearing assemblies68 each including a bearing block 70 having a bearing bore 72 thatreceives a corresponding bearing 74, each bearing 74 including a race 76and a spherical bearing member 78. The spindle attachment plate 62includes a plurality of elongated welding apertures 80 about which aweld is received to weld the bearing blocks 70 to the spindle attachmentplate 62 of the mounting arrangement 50. It is noted that the bearingbore 72 of each of the bearing blocks 70 is machined prior to attachingthe bearing block 70 to the mounting arrangement 50. A kingpin assembly82 including an elongated kingpin collar 84 and a kingpin 86 extendsthrough the bearings 74 and an aperture 88 of the spindle 90, therebypivotably securing the spindle 90 to the axle assembly 20. Specifically,tightening of the kingpin 86 creates a load path extending through thekingpin collar 84, each of the spherical bearing members 78, an end ofthe spindle 90, and a collar member 92. Over-tightening of the kingpin86 is prevented by a washer member 94 positioned between the lower ofthe spherical bearing members 78 and the spindle 90. It is noted thatthe lower of the bearing blocks 70 includes a collar portion 96 thatabuts the race 76 of the corresponding bearing 74, thereby providingproper spacing and assisting during assembly. Specifically, the collarportion or lip 96 provides a stop for the bearing to be pressed toduring assembly, thereby defining the vertical positioning for theentire spindle assembly. Further, the lip 96 is adapted to support thevertical load should the press-fit of the bearing fail. A pair ofretainer plates 98 are secured to the corresponding bearing blocks 70 bya plurality of bolts 100. The hub assemblies 102, breaking assemblies103 and tires 104 are coupled to the associated spindle 90.

Each mounting arrangement 50 (FIGS. 9A and 9B) includes forwardly andrearwardly extending air spring mounting brackets 108 to which thecorresponding air spring assembly 22 (FIG. 5) is coupled. In theillustrated example, the air spring mounting brackets 108 are integratedwith the rest of the associated mounting arrangement, including the rearplate 52, the front plate 54 and the spindle attachment bracket 62. Asbest illustrated in FIG. 13, each air spring assembly 22 includes arolling lobe-style air spring 110 including an air bladder 112, aninternal lobe member 114 and a top plate 116. A mounting plate 118 issecured to the lobe member 114 via a plurality of mechanical fasteners120, with the mounting plate 118 being secured to the air springmounting brackets 108 by a plurality of mechanical fasteners such asbolts 122. The top plate 116 is secured to an upper mounting plate 124by a plurality of mechanical fasteners 126. The upper mounting plate 124is attached to a corresponding vehicle frame rail 14. As bestillustrated in FIG. 14, the mounting arrangements 50 are located andconfigured such that the air spring assemblies 22 are inwardly inclinedfrom the mounting assemblies 50 towards the vehicle frame rails 14 at anangle α, thereby resulting in a lower spring rate and reducing theinteraction between the suspension and chassis and improving the controlin a vehicle jounce event. Further, the incline of the spring assemblies22 reduces the overall travel thereof, thereby allow use of rolling-lobetype air springs and reducing the overall cost. Preferably, angle α isbetween 30° and 45° from vertical, and more preferably between 30° and35° from vertical, thereby resulting in a natural frequency for thevertical displacement or vibrations of the suspension assembly of lessthan or equal to about 3 Hz, and more preferably of between about 1 Hzand 2 Hz.

The outwardly-sweeping configuration of the trailing arms 16, 18 (FIG.12B) in conjunction with the configuration and construction of themounting arrangements 50, provides for attachment of the trailing arms16, 18, the spindles 90, and the air spring assemblies 22 in closeproximity to one another and in close proximity to the ends of the axlemember 20. Preferably, the distance X between the center point of theconnection of the trailing arms 16, 18 with the mounting arrangement 50and the center point of the connection of the spindle 90 with themounting arrangement 50 is less than or equal to about 6 inches, thedistance Y between the center point of the connection between thespindle 90 with the mounting arrangement 50 and the center point of theconnection between the air spring assembly 22 with the mountingarrangement 50 is less than or equal to about 14 inches, and the totallength Z of the mounting arrangement 50 is less than or equal to about20 inches.

As best illustrated in FIGS. 3A and 3B, the vehicle suspension assembly10 is vertically adjustable. Specifically, the axle assembly 20 ismovable from a lowered position A, wherein the tires 104 contact aground surface, thereby assisting and supporting the load of thevehicle, and a raised position B, wherein the tires 104 are spaced fromthe ground surface, thereby reducing tire wear and fuel consumption. Thevehicle suspension assembly 10 includes a pair of lift arrangements 120operably coupled with the associated upper trailing arms 16 and mountingbrackets 12. Each lift arrangement 120 includes a dual diaphragm chamberassembly 122 (FIG. 15A-FIG. 16) including first diaphragm chamber 124and a second diaphragm chamber 126. Each diaphragm chamber 124, 126includes a housing 128 divided into an upper chamber 130 and a lowerchamber 132 by a deformable diaphragm 134 and a push plate 136, whereinthe upper chamber 130 may be pressurized via an air inlet 138. Each pushplate 136 is secured to a push rod 140 such that the push rods 140 areeach forced in a direction 142 as the upper chamber 138 is pressurized.It is noted that in the illustrated example, the longitudinal axis 146of each of the push rods 140 are aligned with one another. It is furthernoted that the dual push rods 140 may be replaced by a single push rodthat extends through both the first diaphragm chamber 124 and the seconddiaphragm chamber 126. The diaphragm chamber assembly 122 is attached toa corresponding upper trailing arm 16 by a lift bracket 148, while thepush rod 140 associated with the second diaphragm chamber 126 ispivotably coupled to an associated mounting bracket 12 by a push rodplate 150 that is fixedly coupled to the mounting bracket 12, and aclevis arrangement 152 that is attached to the end of the push rod 140of the second diaphragm chamber 126 and pivotably coupled to the pushrod plate 150. It is noted that the configuration of the diaphragmchamber assembly 122 results in a beveling of the force exerted on theassociated push rods 150 while maintaining a reduced overall plan arearequired to house or position the diaphragm chamber assembly 122 withinthe overall vehicle suspension assembly 10.

The vehicle suspension assembly 10 further comprises a self-steerassembly which pivots the spindles 90 and the tires 104 between aninline orientation C, as illustrated in FIG. 4A, and a turningorientation B, as illustrated in FIG. 4B. In the illustrated example,the steering assembly 160 includes a tie rod 162 pivotably coupled tospindle arms 164 (FIG. 14) associated with each spindle 90. The steeringassembly 160 further includes a pair of damper assemblies 166 pivotablysecured to the spindle arms 164 and the axle 58 via a pair of mountingbrackets 170 (FIG. 2).

In the foregoing description it will be readily appreciated by thoseskilled in the art that modifications may be made to the inventionwithout departing from the concepts as disclosed herein. Suchmodifications are to be considered as included in the following claims,unless these claims by their express language state otherwise.

The invention claimed is:
 1. A vehicle suspension assembly, comprising:an axle member having a first end and a second end, the axle membermovable between a first position, wherein at least one tire coupled withthe axle member contacts a ground surface, and a second position,wherein the at least one tire is spaced from the ground surface; a firstmounting bracket adapted to couple to a vehicle frame assembly; a firsttrailing arm having a first end pivotably coupled to the first mountingbracket, and a second end pivotably coupled to the first end of the axlemember; a second mounting bracket adapted to couple to a vehicle frameassembly; a second trailing arm having a first end pivotably coupled tothe second mounting bracket, and a second end pivotably coupled to thesecond end of the axle member; a first lift arrangement, comprising: afirst diaphragm chamber having a first push plate and a flexiblebladder, the first push plate of the first diaphragm chamber dividingthe first diaphragm chamber into a first compartment and a secondcompartment, the first compartment of the first diaphragm chamber beingadjustably pressurized to move the first push plate of the firstdiaphragm chamber; a second diaphragm chamber having a second push plateincluding a flexible bladder, the second push plate of the seconddiaphragm chamber dividing the second diaphragm chamber into a firstcompartment and a second compartment, the first compartment of thesecond diaphragm chamber being adjustably pressurized to move the secondpush plate of the second diaphragm chamber; and at least one push roddefining a single longitudinal axis and connected to the first pushplate and the second push plate such that pressurization of the firstand second diaphragm chambers cause a translational movement of the atleast one push rod, wherein the at least one push rod is operablycoupled with the vehicle suspension assembly such that translationalmovement of the at least one push rod causes the axle member to movebetween the first and second positions, wherein an overall length of theat least one push rod remains substantially constant as the axle membermoves between the first and second positions and wherein the first pushplate and the second push plate are configured to move in the samedirection as the axle member moves between the first and secondpositions.
 2. The vehicle suspension assembly of claim 1, wherein thefirst lift arrangement is connected to a lift bracket, and wherein thelift bracket is pivotably coupled to the first trailing arm.
 3. Thevehicle suspension assembly of claim 2, wherein the at least one pushrod is pivotably coupled to a push rod plate that is fixedly coupled tothe first mounting bracket.
 4. The vehicle suspension assembly of claim1, wherein the at least one push rod comprises a first push rodconnected to the first push plate and a second push rod connected to thesecond push plate.
 5. The vehicle suspension assembly of claim 1,further comprising: a second lift arrangement, comprising: a firstdiaphragm chamber having a first push plate and a flexible bladder, thefirst push plate of the first diaphragm chamber of the second liftarrangement dividing the first diaphragm chamber of the second liftarrangement into a first compartment and a second compartment, the firstcompartment of the first diaphragm chamber of the second liftarrangement being adjustably pressurized to move the first push plate ofthe first diaphragm chamber of the second lift arrangement; a seconddiaphragm chamber having a second push plate including a flexiblebladder, the second push plate of the second diaphragm chamber of thesecond lift arrangement dividing the second diaphragm chamber of thesecond lift arrangement into a first compartment and a secondcompartment, the first compartment of the second diaphragm chamber ofthe second lift arrangement being adjustably pressurized to move thesecond push plate of the second diaphragm chamber of the second liftarrangement; and at least one push rod defining a single longitudinalaxis connected to the first push plate and the second push plate of thesecond lift arrangement such that pressurization of the first and seconddiaphragm chambers cause a translational movement of the at least onepush rod of the second lift arrangement, wherein the at least one pushrod of the second lift arrangement is operably coupled with the vehiclesuspension assembly such that translational movement of the at least onepush rod of the second lift arrangement causes the axle member to movebetween the first and second positions.
 6. The vehicle suspension systemassembly of claim 5, wherein the at least one push rod of the secondlift arrangement comprises a first push rod connected to the first pushplate of the second lift arrangement and a second push rod connected tothe second push plate of the second lift arrangement.
 7. The vehiclesuspension assembly of claim 1, further comprising: a steeringarrangement operably coupled with at least a select one of the first andsecond spindle assemblies, and adapted to move a tire coupled to one ofthe spindle assemblies between a first position defining a firstdirection of travel, and a second position defining a second directionof travel that is different than the first direction of travel.
 8. Avehicle suspension assembly, comprising: an axle assembly having a firstend and a second end; a first mounting bracket and a second mountingbracket each adapted to couple to a vehicle frame assembly; a firsttrailing arm having a first end pivotably coupled to the first mountingbracket, and a second end pivotably coupled to the first end of the axleassembly; a second trailing arm having a first end pivotably coupled tothe second mounting bracket, and a second end pivotably coupled to thesecond end of the axle assembly; a first air spring assembly coupled toa first end of the axle assembly such that a longitudinal axis of thefirst air spring assembly inclines inwardly from the first end of theaxle assembly; a second air spring assembly coupled to the second end ofthe axle assembly such that a longitudinal axis of the second air springassembly inclines inwardly from the second end of the axle assembly;wherein a natural frequency of the suspension assembly is less than orequal to about 3 Hz.
 9. The vehicle suspension assembly of claim 8,wherein the natural frequency of the suspension assembly is betweenabout 1 Hz and 2 Hz.
 10. The vehicle suspension assembly of claim 8,wherein the first and second air spring assemblies are angled at between30° and 45° from vertical.
 11. The vehicle suspension assembly of claim10, wherein the first and second air spring assemblies are angled atbetween 30° and 35° from vertical.
 12. The vehicle suspension assemblyof claim 8, further comprising: a lift arrangement operably coupled withat least one of the first trailing arm and the second trailing arm, andadapted to move the axle between a first vertical position, wherein atire coupled to one of the ends of the axle member contacts a groundsurface, and a second vertical position, wherein the tire is spaced fromthe ground surface.
 13. The vehicle suspension assembly of claim 12,further comprising: a first spindle assembly coupled with the first endof the axle assembly and a second spindle assembly coupled with thesecond end of the axle assembly; and a steering arrangement operablycoupled with at least a select one of the first and second spindleassemblies, and adapted to move a tire coupled to one of the spindleassemblies between a first position defining a first direction oftravel, and a second position defining a second direction of travel thatis different than the first direction of travel.
 14. The vehiclesuspension assembly of claim 8, further comprising: a first spindleassembly coupled with the first end of the axle assembly and a secondspindle assembly coupled with the second end of the axle assembly; and asteering arrangement operably coupled with at least a select one of thefirst and second spindle assemblies, and adapted to move a tire coupledto one of the spindle assemblies between a first position defining afirst direction of travel, and a second position defining a seconddirection of travel that is different than the first direction oftravel.
 15. The vehicle suspension of claim 8, wherein the axle assemblyincludes an integrated first mounting arrangement coupled to the firstend of the axle member, wherein the mounting arrangement couples thefirst end of the axle member to a first spindle assembly, and whereinthe first air spring is coupled to the mounting arrangement.
 16. Thevehicle suspension of claim 15, wherein the mounting arrangementpivotably couples the second end of the first trailing arm to the firstend of the axle member.
 17. A vehicle suspension assembly, comprising:an axle member having a first end and a second end, the axle membermovable between a first position, wherein at least one tire coupled withthe axle member contacts a ground surface, and a second position,wherein the at least one tire is spaced from the ground surface; a firstmounting bracket coupled to a vehicle frame assembly; a first trailingarm having a first end pivotably coupled to the first mounting bracket,and a second end pivotably coupled to the first end of the axle member;a second mounting bracket adapted to couple to a vehicle frame assembly;a second trailing arm having a first end pivotably coupled to the secondmounting bracket, and a second end pivotably coupled to the second endof the axle member; a first lift arrangement, comprising: a firstdiaphragm chamber having a first push plate and a flexible bladder, thefirst push plate of the first diaphragm chamber dividing the firstdiaphragm chamber into a first compartment and a second compartment, thefirst compartment of the first diaphragm chamber being adjustablypressurized to move the first push plate of the first diaphragm chamber;a second diaphragm chamber having a second push plate including aflexible bladder, the second push plate of the second diaphragm chamberdividing the second diaphragm chamber into a first compartment and asecond compartment, the first compartment of the second diaphragmchamber being adjustably pressurized to move the second push plate ofthe second diaphragm chamber; and at least one push rod defining asingle longitudinal axis and connected to the first push plate and thesecond push plate such that pressurization of the first and seconddiaphragm chambers cause a translational movement of the at least onepush rod, wherein the at least one push rod is operably coupled with thevehicle suspension assembly such that translational movement of the atleast one push rod causes the axle member to move between the first andsecond positions, and wherein the first diaphragm chamber and the seconddiaphragm chamber are both fixed with respect to a select one of thefirst trailing arm and the vehicle frame assembly.
 18. The vehiclesuspension assembly of claim 17, wherein the first diaphragm chamber andthe second diaphragm chamber are both fixed with respect to the vehicleframe assembly.